This invention relates generally to a security system for the deterrence of theft of electrical appliances or other property with electrical circuitry and more particularly to a security system which deters by limiting the operability of electrical appliances or other items with electrical circuitry to the perimeters of a specified zone.
Various security systems exist within the prior art for the prevention of theft of property. One such system is disclosed in Bernhardt U.S. Pat. No. 4,559,529 in which radio signals are transmitted to protect monitored articles. An audible alarm is triggered if an improper code is received. Whalen, et al. U.S. Pat. No. 3,710,371 disclose a system which employs a mercury switch to energize an alarm, and the systems disclosed in Lent U.S. Pat. No. 4,284,983 and Matto, et al. U.S. Pat. No. 3,836,901 sound alarms if there is unauthorized disconnection of the monitored appliance and the appliance is moved from its original position. In addition, security systems disclosed in Manley, et al. U.S. Pat. No. 3,794,989 and Cline U.S. Pat. No. 3,484,775 trigger alarms when a monitored appliance is disconnected, and Boyd, et al. U.S. Pat. No. 4,573,042 and Antenore U.S. Pat. No. 4,136,338 disclose systems which sound alarms when physical parameters have been exceeded by a monitored appliance.
While the prior art provides various security systems for designated articles, there exists a need for a theft prevention system for electrical items with an effective deterrent alternative.